This study is designed to evaluate duloxetine for the treatment of fibromyalgia syndrome patients.

Inclusion Criteria:

• Meet criteria for primary fibromyalgia syndrome as defined by the American College of Rheumatologists

Exclusion Criteria:

• Treatment with a monoamine oxidase inhibitor within 14 days prior to Visit 2 or the potential need to take within 5 days after discontinuation from the study.
• Any patients judged by their physicians to be at serious suicidal risk.
• Have uncontrolled narrow-angle glaucoma